It could well be that Canada never decides what it really wants from China.

With its decision to block a $1.5-billion takeover of Aecon Group Inc., the construction company, by China Communications Construction Co. Ltd. (CCCC), the federal government has shown that its frequent assertions that it welcomes Chinese investment have some rather crucial caveats.

They are: Subject to fears about foreign state control and foreign state spying to be decided at a later date. Canadian companies seeking investments to compete against global majors, as Aecon did, will now be as reluctant to invite such bids from Chinese multinationals as those firms will be to make them.

Story continues below advertisement

It’s been a very long and confusing process to get to this outcome. It leaves Aecon shareholders with no shortage of uncertainty regarding the value of their stock. Even before Ottawa announced its decision on Wednesday, the shares had slumped well below the CCCC offer of $20.37 on growing worries about just such an outcome.

To recap: Aecon, known for major construction projects across Canada as well as nuclear power plant refurbishment, agreed to be acquired by state-controlled CCCC, one of the world’s largest infrastructure companies, following an auction last October.

Aecon’s chief executive officer, John Beck, said the company had been hamstrung in its ability to win major contracts. By becoming part of a global heavyweight, it would mean it could be in the running to win more big construction jobs and hire more workers. For that reason, Canada’s Building Trades Unions supported the takeover.

A similar deal by CCCC – its takeover of John Holland Group Pty Ltd. in 2015 – went swimmingly and more Australians keep getting hired, Mr. Beck said.

Story continues below advertisement

The deal drew fire from several quarters, including rival construction companies, which raised corruption, safety and national security concerns, especially related to the nukes. Major competitors PCL Constructors Inc., Ledcor Group and P.W. Graham & Sons Construction met with senior bureaucrats to press their case.

In a bizarre episode of guerilla theatre, a man called Michael Beattie made the rounds in Ottawa to fire shots at the transaction, only to be revealed, not as the successful construction executive he claimed to be, but as a flimflam man who had previously been convicted of fraud and perjury.

After months of being coy on whether the takeover would be subject to a full security review under the Investment Canada Act, The Liberals decided one was warranted, and the research was prolonged.

In a last-ditch attempt to win over government and public support early this month, Mr. Beck and CCCC President Lu Jianzhong wrote an op-ed in The Globe and Mail to blast the “false claims” of their opponents, which they said were based on “political opinion and a desire to limit competition.”

Now, the deal’s history and for Canada, it’s back to figuring out what it actually wants from China amid frets about intellectual property theft and spying – plus general trade angst as it relates to the Communist country, where human rights abuses still get swept under the rug. Indeed, in the hours following the Ottawa’s bombshell on Wednesday, warnings sounded that China will mount some form of retaliation.

These decisions by Ottawa defy prediction. Just last year, Ottawa approved the acquisition of Vancouver high-tech firm Norsat International Inc. by China’s Hytera Communications Corp. It received a routine screening in Canada. That rankled the U.S. Defence Department, for which Norsat had contracts.

Story continues below advertisement

It’s not just the Trudeau Liberals sending mixed messages to the trading partner that’s often touted as the biggest opportunity to expand exports beyond the United States. Recall the gnashing of teeth among the governing Conservatives of Stephen Harper that accompanied the review of CNOOC Ltd.’s $15.1-billion takeover of Calgary-based Nexen Inc. in 2012. Mr. Harper approved the sale, which included Nexen’s Long Lake oil sands project in Alberta. But he slammed the brakes on state-owned enterprises buying control of any more oil sands projects, fearing foreign governments could take all the spoils.

As it happened, the Chinese SOEs took Ottawa’s restrictions as a cue to refrain from buying other types of energy projects as well, and the deal flow dried up. The death of the Aecon deal shows that it’s still very much a toss-up whether Canadian companies should bother trying to woo Chinese capital.

Prime Minister Justin Trudeau says he accepts the recommendation from intelligence agencies that a proposed takeover of construction firm Aecon Group Inc. by a Chinese state-owned company is not in the interest of national security.The Canadian Press

Due to technical reasons, we have temporarily removed commenting from our articles. We hope to have this fixed soon. Thank you for your patience. If you are looking to give feedback on our new site, please send it along to feedback@globeandmail.com. If you want to write a letter to the editor, please forward to letters@globeandmail.com.

Welcome to The Globe and Mail’s comment community. This is a space where subscribers can engage with each other and Globe staff. Non-subscribers can read and sort comments but will not be able to engage with them in any way. Click here to subscribe.

Welcome to The Globe and Mail’s comment community. This is a space where subscribers can engage with each other and Globe staff. Non-subscribers can read and sort comments but will not be able to engage with them in any way. Click here to subscribe.